Sorry, I just noticed this post. I only warned of feeding rosy reds too often because many people get into the habit of feeding their aquatic turtles feeder fish and don't offer enough variety. It is so convenient to stop at the local pet store and pick up a bunch of fish for fairly cheap, drop them in the tank, and know that the turtle will have some food for the next few days.
I studied some problems that can occur from feeding any herp, or other animal for that matter, too much fish. It's been a fairly long time, but I faintly remember two key elements that play a role...vitamin B and taurine(tuarine?). Vitamin B deficiencies can develop, and too much taurine can actually cause an animal to have hyperactive digestion. When I worked at a nature museum, an egret that we had would only eat fish. We used to place Vitamin B and D tablets inside the fish for supplementation. It would have been better to vary the diet, but the bird had been seriously injured by a boater and was seriously brain damaged. NOTE - I DO NOT recommend placing vitamin D and B supplements in fish destined for herps. This was a veterinary prescribed practice for this bird only! Use supplements specifically designed for the herp of choice.
Your success is no doubt due to the fact that you offered a variety of food, along with other good husbandry practices. This is always the best course of action. Plus, it's fun to watch them explore new food items.